@@ -316,7 +316,7 @@ func (s *DockerSwarmSuite) TestAPISwarmLeaderElection(c *testing.T) {

 		followers []*daemon.Daemon // keep track of followers

 	)

 	var lastErr error

-	checkLeader := func(nodes ...*daemon.Daemon) interface{} {

+	checkLeader := func(nodes ...*daemon.Daemon) checkF {

 		return func(c *testing.T) (interface{}, string) {

 			// clear these out before each run

 			leader = nil

@@ -413,41 +413,12 @@ func getErrorMessage(c *testing.T, body []byte) string {

 	return strings.TrimSpace(resp.Message)

 }

-func waitAndAssert(t *testing.T, timeout time.Duration, f interface{}, comparison interface{}, args ...interface{}) {

-	t1 := time.Now()

-	defer func() {

-		t2 := time.Now()

-		t.Logf("waited for %v (out of %v)", t2.Sub(t1), timeout)

-	}()

-

-	after := time.After(timeout)

-	for {

-		v, comment := f.(checkF)(t)

-		args = append([]interface{}{v}, args...)

-		shouldAssert := assert.Check(t, comparison, args...)

-		select {

-		case <-after:

-			shouldAssert = true

-		default:

-		}

-		if shouldAssert {

-			if len(comment) > 0 {

-				args = append(args, comment)

-			}

-			assert.Assert(t, comparison, args...)

-			return

-		}

-		time.Sleep(100 * time.Millisecond)

-	}

-}

-

 type checkF func(*testing.T) (interface{}, string)

 type reducer func(...interface{}) interface{}

-func pollCheck(t *testing.T, f interface{}, compare func(x interface{}) assert.BoolOrComparison) poll.Check {

+func pollCheck(t *testing.T, f checkF, compare func(x interface{}) assert.BoolOrComparison) poll.Check {

 	return func(poll.LogT) poll.Result {

-		ff := f.(checkF)

-		v, comment := ff(t)

+		v, comment := f(t)

 		if assert.Check(t, compare(v)) {

 			return poll.Success()

 		}

@@ -455,12 +426,12 @@ func pollCheck(t *testing.T, f interface{}, compare func(x interface{}) assert.B

 	}

 }

-func reducedCheck(r reducer, funcs ...interface{}) checkF {

+func reducedCheck(r reducer, funcs ...checkF) checkF {

 	return func(c *testing.T) (interface{}, string) {

 		var values []interface{}

 		var comments []string

 		for _, f := range funcs {

-			v, comment := f.(checkF)(c)

+			v, comment := f(c)

 			values = append(values, v)

 			if len(comment) > 0 {

 				comments = append(comments, comment)